Game ball incorporating a polymer foam

Abstract

A game ball is disclosed that includes a polymer foam layer processed with an inert fluid blowing agent, such as nitrogen. The polymer foam may be a polyolefin material, such as polyethylene, polypropylene, and ethylvinylacetate, and the inert fluid blowing agent may have a relatively high-purity. The polymer foam may be manufactured with a process that includes impregnating a polymer with the inert fluid blowing agent and expanding the polymer by heating the polymer above a softening temperature of the polymer, reducing a fluid pressure surrounding the polymer, and cooling the polymer. The game ball may be a soccerball, football, or volleyball, for example, that includes the polymer foam.

1. A soccerball comprising:
 a cover that forms an exterior surface of the soccerball, the cover including a plurality of panels connected along abutting edges; 
 a foam layer located adjacent to the cover, the foam layer including a closed cell, cross-linked, foam processed with a nitrogen blowing agent having at least 99.9% purity, the foam layer having a thickness ranging from 0.5 to 4.5 mm, wherein a material of the foam layer is selected from a group consisting of low-density polyethylene, high-density polyethylene, polypropylene and ethylvinylacetate; 
 a textile layer located adjacent to the foam layer, the textile layer including at least one textile material; and 
 an inflatable bladder located adjacent to the textile layer; 
 wherein the soccerball has a rebound ranging from 138 to 140 cm; a size expansion of from 0.54 to 0.66 cm. 
 
   
   
     2. The soccerball of  claim 1 , wherein the foam layer is manufactured through a process that includes:
 providing a polymer, 
 impregnating the polymer with a nitrogen blowing agent having at least 99.9% purity, and 
 expanding the polymer by heating the polymer above a softening temperature of the polymer, reducing a fluid pressure surrounding the polymer, and cooling the polymer to form the closed cell, cross-linked, foam. 
 
   
   
     3. The soccerball of  claim 1 , wherein the panels include twenty hexagonal panels and twelve pentagonal panels.